The present invention is a system for providing a model of groundwater flow based on real time groundwater data. Specifically, the present invention is a system for collecting real time groundwater data and processing same to form a model of the groundwater flow which is graphically depicted in three dimensions.
Increased use and importance of groundwater as a source of municipal water supplies has increased the need for understanding and managing groundwater resources. The 1986 amendments to the federal Safe Drinking Water Act focus on protecting municipal well fields through the designation of wellhead protection ground regions thereabout and the management of the included subsurface and surface areas. A wellhead protection area (WHPA) is defined as a surface and the region therebelow down to the aquifer (usually termed the subsurface area) surrounding a public well or well field. This is the region through which contaminants are likely to move toward and reach the well or well field. By delineating the WHPA, contaminant sources within the WHPA can be managed to eliminate or attenuate their impact on well water quality.
The promulgation of environmental regulations and laws governing industries, businesses and individuals has created a need for a wide range of services related to the development, management, assessment and protection of groundwater resources. A successful wellhead protection program involves the following elements: 1) inventorying sources of contamination; 2) delineating the wellhead protection area; 3) developing a strategy for managing sources of contamination; 4) assessing well and aquifer vulnerability; 5) developing a scheme for monitoring groundwater quality in the WHPA; and 6) developing contingency plans in the event of well field contamination. Geographic information systems (GIS) provide a powerful tool for the development and presentation of each of the components of a wellhead protection strategy.
A GIS, which includes data, hardware, software and users, is a computerized, integrated system used to compile, store, manipulate and output mapped spatial data. A GIS may be used to quickly access an integrated, geographically-referenced database of attributes for creating a map that can be overlaid, combined, manipulated and analyzed to user specifications. Many people have utilized a GIS for the storage and processing of environmental data. Specifically, a GIS has been used to link a previously existing groundwater flow models with newly obtained data from the corresponding WHPA, such that the resulting model output could be integrated within the GIS database from which further maps can be generated for that specific WHPA. In addition, the resulting model within the GIS database can be used with varying data set inputs for multiple model runs, or to provide inputs for a number of other different models. The ability to link groundwater flow models and GIS databases to create three-dimensional representations of corresponding geological and hydrological systems is also known.
The groundwater industry, including businesses for groundwater supply management and the management of groundwater resources, relies on classical hydrogeologic principles to characterize aquifer flow systems. The accuracy of the output results for computed groundwater flows based on measured data and the mathematical calculations specified by a model are limited by the quality and accuracy of the input data. In addition, the mathematics and physics associated with classic hydrogeologic principles often assume conditions for convenience or mathematical tractability that do not exist in reality. The present status of hydrogeologic assessments of groundwater flow typically involves the installation of wells that enable the monitoring of aquifer responses to stress (e.g., pumping). Aquifer parameters, including hydraulic conductivity, transmissivity, and storativity have historically been estimated or calculated through aquifer testing over a relatively short time period (hours to a few days). More recently, these data have been utilized in numerical and analytical groundwater flow models which provide long-term simulations of aquifer behavior. Unfortunately, the methods for data collection have not progressed at the same rate as the computer applications, particularly with respect to long-term characterization of flow.
Often, the data collected to characterize aquifer systems represents a relatively small "snapshot in time" of the aquifer response to stress. As a result of this process, errors accumulate during the modeling task based on this data due to anisotropy, heterogeneity and boundaries affecting flow conditions in the WHPA not apparent during the short-term aquifer tests. These errors could be greatly reduced by providing a mechanism for collecting real time data directly from remote locations continually and providing a model of the flow over time giving results that can be graphically depicted over the long-term data for analysis and interpretation.